<template>
   <div class="todo-footer">
        <label>
          <input type="checkbox" @click="handleCheckAll" :checked="allCheck"/>
        </label>
        <span>
          <span>已完成{{doneCount}}</span> / 全部{{total}}
        </span>
        <button class="btn btn-danger" @click="deleteOne">清除已完成任务</button>
  </div>
</template>

<script>
  export default {
    name:'Footer',
    props:['deleteOne','todos','checkAll'],
    computed: {
      doneCount(){
        return this.todos.filter(todos => todos.done).length
      },
      total(){
        return this.todos.length
      },
      allCheck(){
        return (this.doneCount === this.total) && (this.total > 0) 
      }
    },
    methods:{
      handleCheckAll(e){
        // 这里是通知App去全选  还是  全不选
        this.checkAll(e.target.checked)
      }
    }
  }
</script>

<style scoped>
  /*footer*/
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}
</style>